Please can you explain how Ryanair can retain its fifth freedom rights, yet British airlines will lose theirs just because the EU says so. Don't air routes around the world come under the Chicago Convention, which the EU is not even a member?512
You are incorrect in your assumption.
Ryanair is making changes to its operation model to ensure flights in UK under fifth freedom rights, if those rights are abolished, are maintained.
The UK AOC allows for UK flights in such case, EI AOC will then not be used on those routes.
British airlines are able to do the same, by setting up EU subsidiaries, as easyJet has done.